I miss my kids altogether, since they live away. But I'm taking kind of hard the fact my oldest is going in the other direction for college, so he'll be even less accessible.
I don't miss the kids being BABIES... ugh... that was a hard time. But there was a real delight when they were 3-6 or so; they still needed care and oversight, but they were just fun, and always around, and they were learning so much, and that's a time when parents can be involved.
After that age, school and friends take more priority. As teens, they've got their own lives, and I feel more distant.

It's funny how all that goes, and hard to believe how fast it went.